This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A246300 #7 Jan 20 2025 13:25:44 %S A246300 5,12,18,24,30,37,43,49,56,62,68,74,81,87,93,100,106,112,118,125,131, %T A246300 137,144,150,156,162,169,175,181,187,194,200,206,213,219,225,231,238, %U A246300 244,250,257,263,269,275,282,288,294,301,307,313,319,326,332,338,345 %N A246300 Numbers k such that cos(k) < cos(k+1) > cos(k+2). %C A246300 The sequences A026311, A246300, A246301, A246302 partition the nonnegative integers. %H A246300 Clark Kimberling, <a href="/A246300/b246300.txt">Table of n, a(n) for n = 1..1000</a> %t A246300 z = 520; f[x_] := f[x] = Cos[x]; t = Range[0, z]; %t A246300 Select[t, f[#] > f[# + 1] &] (* A026311 *) %t A246300 Select[t, f[#] < f[# + 1] > f[# + 2] &] (* A246300 *) %t A246300 Select[t, f[#] < f[# + 1] < f[# + 2] > f[# + 3] &] (* A246301 *) %t A246300 Select[t, f[#] < f[# + 1] < f[# + 2] < f[# + 3] > f[# + 4] &] (* A246302 *) %t A246300 Flatten[Position[Partition[Cos[Range[350]],3,1],_?(#[[1]]<#[[2]]>#[[3]]&),1,Heads->False]] (* _Harvey P. Dale_, Jan 20 2025 *) %Y A246300 Cf. A246294, A026311, A246301, A246302. %K A246300 nonn,easy %O A246300 1,1 %A A246300 _Clark Kimberling_, Aug 22 2014